Multi-link conveyor chains are in widespread use in the glass industry for transporting glass products between processing stations. For example, a multi-link conveyor chain which is typically 100 feet long may be used to transport blown glass from a blowing station to an annealing station. A multi-link conveyor chain may be used to transport small glassware such as perfume bottles, wine glasses, pharmaceutical glassware and decorated medicine bottles.
In one conventional multi-link conveyor chain, there is a plurality of parallel spaced apart elongate pins having an oval-shaped cross-section. Mounted on adjacent elongate pins are a series of link plates spaced apart along the pin by a plurality of washers, each link plate comprising a first and a second link. Each of the first and second links is capable of engaging a drive sprocket and has an oval-shaped aperture for receiving the elongate pin. The multi-link conveyor chain is driven by the engagement of the links of the link plate with the multiple teeth of a drive sprocket during a cycle of engagement. The conventional multi-link conveyor chain is assembled so that each end of the elongate pin extends beyond the outermost link plate (i.e. beyond the edge of the flat conveyor surface) and a pin head is fixed to each exposed end. Each end of the elongate pin is secured in a protective enclosure member (e.g. a head protector) that has a countersink to accommodate a pin head such that the pin head does not protrude from the enclosure member. One such arrangement is described in EP-A-1241117.
In the arrangement described in EP-A-1241117 and in other conventional arrangements described in inter alia EP-A-2368816, WO-A-2004/043833, US-A-2009/242360, US-A-2009/277758, U.S. Pat. No. 5,957,268, DE1044707 and U.S. Pat. No. 6,036,002, the protective enclosure member is equipped with twin bores to couple adjacent elongate pins.
The multi-link conveyor chain known as LIFEGUARD™ is a side guide conveyor chain which deploys interlocking enclosure members to provide a gap-free side profile.